Ground running
While you are doing the engineers licence course on the particular type of aircraft you will have several sessions in the simulator. If you are very luck you get the full motion one but normally it is the fixed base type.
During the sessions all the procedures are gone through, including problems, with the instructor putting faults in to the system to get you to trouble shoot. At the end of the course you are licenced to carry out all the relevent tasks on the aircraft, including engine runs at what ever power is necessary.
All the info is in the AMM together with safety items, such as only running two engines (on a 4 engine A/C) at a high power one on either wing with the opposite one to the problem at a mid power range for balance reasons.
You have to realise that when running at significant power the aircraft is jumping about quite a bit and it may not be obvious that you are moving initally.
tristar 500